[FIX] point_of_sale: force no-tax on demo product

The javascript tour (test) will verify the total amount based on sale
price of the product without taking taxes into account.
However, if any l10n_* module is installed and defined a default value
for product taxes, the test will fail this check.

addons/point_of_sale/data/point_of_sale_demo.xml

@@ -141,6 +141,7 @@
           <field name="uom_id" ref="product.product_uom_kgm" />
           <field name="uom_po_id" ref="product.product_uom_kgm" />
           <field name="image" type="base64" file="point_of_sale/static/img/peche-image.jpg"/>
+          <field name="taxes_id" eval='[(5,)]'/>  <!-- no taxes -->
         </record>
 
         <record id="raisins_noir" model="product.product">